Fibromyalgia

By Dr Simon Kyle

Fibromyalgia (also know as fibromyalgia syndrome) is principally characterized by chronic widespread pain, fatigue and heightened response to tactile pressure. This chronic condition results in marked daytime distress and dysfunction. Poor, non-restorative sleep and insomnia are very common in patients with fibromyalgia (in as many as 95% of diagnosed patients), along with impairments in cognition (especially concentration and memory), headaches, and depression.

Causes of fibromyalgia
Approximately 2-4% of the population experience fibromyalgia, and the condition is more common in women. Although the underlying cause(s) of fibromyalgia is not yet clear, a number of theories exist, and include altered pain processing, changes in levels of specific neurotransmitters, stress reactivity, and psychological factors.

Objective changes to sleep have been documented, most commonly reflected in increased alpha activity (alpha intrusions) during NREM sleep, thought to indicate the presence of hypervigilance during sleep. Reduced slow-wave (deep) sleep has also been reported.

As problems with initiating and maintaining sleep are very common in patients with fibromyalgia, research has been conducted to see if cognitive behavioral methods for insomnia (CBT-I) can be applied to this patient group. One study published in 2005 found that individual CBT in fibromyalgia patients led to a 50% reduction in wake time during the night and roughly 60% of treated patients had a clinically important improvement in insomnia symptoms (Edinger et al., 2005). What still needs to be determined is whether improving sleep can have meaningful changes to the experience of pain, fatigue and other measures of well-being and quality of life.

The broader relationship between sleep and pain is also an important area of ongoing research. For example, it has been shown that both restricting sleep time and fragmenting sleep in healthy adults can lead to increased pain sensitivity, supporting a potential bi-directional relationship between pain and sleep: pain can disturb sleep, and fragmented sleep can exacerbate daytime pain. Indeed, it was recently shown that those with chronic sleep disturbance (without a diagnosed pain disorder) have altered sensitivity to experimentally-induced pain (Haack et al., 2012).